The Prevalence of Trichinella spiralis in Domestic Pigs in China: A Systematic Review and Meta-Analysis

SIMPLE SUMMARY: As a pathogen of trichinellosis, Trichinella spiralis is a foodborne zoonotic nematode that can infect more than 100 species including mammals, birds, and reptiles. Pigs infected with T. spiralis are the primary host for disseminating it to humans. Therefore, a meta-analysis was performed here to assess the prevalence of T. spiralis in domestic pigs in China. After considering 43 different studies, including a total sample size of 551,097 pigs, these results indicated that T. spiralis were still prevalent in some areas in China and the highest prevalence region was Guangxi. ABSTRACT: The meta-analysis was performed to assess the prevalence of T. spiralis in domestic pigs in China. The potential studies from seven databases (Pubmed, Web of science, Scopus, Google Scholar, CNKI, Wanfang, CBM) were searched. I(2), Cochran’s Q statistic and the funnel plot and Egger’s test were used to assess heterogeneity and publication bias, respectively. In this study, a total of 179 articles were captured in the initially screened. Of these, we finally obtained 39 significant articles (including 43 studies involving in 551,097 pigs) for the final analysis. We calculated using a random-effects model, and we found the overall infection rate was 0.04 (95% CI 0.03–0.06). The highest prevalence region was Guangxi. The funnel plot and Egger’s test showed no publication bias in our meta-analysis. In addition, this high heterogeneity index was suggestive of potential variations which could be due to regions, quality scores, detection methods, publication years, or samplings. These results indicated that T. spiralis were still prevalent in some areas in China. This highlights the need for an increased focus on implementing affordable, appropriate control programs to reduce economic losses and T. spiralis infection in domestic pigs in China.